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拉普拉斯变换方法解分数阶微分方程 被引量:16
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作者 王学彬 《西南师范大学学报(自然科学版)》 CAS 北大核心 2016年第7期7-12,共6页
给出了两种常见分数阶导数即Riemann-Liouville分数阶导数和Caputo分数阶导数的拉普拉斯变换公式,并给出具体实例说明如何利用拉普拉斯变换求解分数阶微分方程和分布阶微分方程.
关键词 Riemann-Liouville分数阶导数 CAPUTO分数阶导数 拉普拉斯变换 分数阶微分方程 分布阶微分方程
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(G′/G)-Expansion Method for Solving Fractional Partial Differential Equations in the Theory of Mathematical Physics 被引量:16
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作者 郑滨 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第11期623-630,共8页
In this paper, the (G′/G)-expansion method is extended to solve fractional partial differential equations in the sense of modified Riemann-Liouville derivative. Based on a nonlinear fractional complex transformation,... In this paper, the (G′/G)-expansion method is extended to solve fractional partial differential equations in the sense of modified Riemann-Liouville derivative. Based on a nonlinear fractional complex transformation, a certain fractional partial differential equation can be turned into another ordinary differential equation of integer order. For illustrating the validity of this method, we apply it to the space-time fractional generalized Hirota-Satsuma coupled KdV equations and the time-fractional fifth-order Sawada-Kotera equation. As a result, some new exact solutions for them are successfully established. 展开更多
关键词 (G'/G)-expansion method fractional partial differential equations exact solutions fractionalcomplex transformation
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基于空间分数阶偏微分方程的图像去噪模型研究 被引量:13
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作者 黄果 许黎 +1 位作者 陈庆利 蒲亦非 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2012年第2期91-98,共8页
为了在获取更高信噪比的同时更多地保留图像边缘和纹理等细节信息,将分数阶微积分理论和偏微分方程方法有效结合,构建了基于空间分数阶偏微分方程的图像去噪模型,并利用分数阶微分掩模算子来实现去噪模型的数值计算。该去噪模型通过引... 为了在获取更高信噪比的同时更多地保留图像边缘和纹理等细节信息,将分数阶微积分理论和偏微分方程方法有效结合,构建了基于空间分数阶偏微分方程的图像去噪模型,并利用分数阶微分掩模算子来实现去噪模型的数值计算。该去噪模型通过引入以分数阶梯度模值为参数的边缘停止函数并选择合适的分数阶微分阶次,由此能够在一定程度上解决传统去噪模型存在的不足之处。实验结果表明,基于空间分数阶偏微分方程的图像去噪模型较传统的去噪模型不仅可以提高图像的信噪比,而且可以更好地保留图像边缘和纹理等细节信息。 展开更多
关键词 分数阶微积分 偏微分方程 分数阶微分掩模 分数阶全变差 图像去噪 信噪比
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一类分数阶微分方程三点边值问题正解的存在性和多重性 被引量:13
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作者 汤小松 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第4期385-392,400,共9页
利用积分方程技巧和锥上不动点指数理论,研究了一类非线性分数阶微分方程的三点边值问题,获得了该问题至少存在1个或2个正解的一系列充分条件.所得结果推广了整数阶微分方程的相应结果.最后,举例说明了所得结果的有效性.
关键词 分数阶微分方程 三点边值问题 不动点指数 正解 存在性
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一种自适应分数阶偏微分图像增强模型 被引量:12
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作者 李伟凯 王政霞 蒋伟 《计算机工程与科学》 CSCD 北大核心 2018年第4期699-706,共8页
针对传统的自适应分数阶偏微分方程图像增强算法对图像暗区纹理区域的增强不足的缺点,考虑到人眼对光感的敏感程度不同,将亮度对视觉的影响因素考虑进传统的自适应分数阶偏微分方程图像增强算法。以梯度和灰度值为参数,建立了一种新的... 针对传统的自适应分数阶偏微分方程图像增强算法对图像暗区纹理区域的增强不足的缺点,考虑到人眼对光感的敏感程度不同,将亮度对视觉的影响因素考虑进传统的自适应分数阶偏微分方程图像增强算法。以梯度和灰度值为参数,建立了一种新的自适应分数阶偏微分图像增强模型。该模型改善了传统算法对暗区图像增强不足的缺点,图像增强后的平均梯度提升明显,很好地改善了图像的视觉效果。实验结果说明本算法具有一定的有效性。 展开更多
关键词 图像增强 分数阶 自适应 偏微分方程 暗区图像增强
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一类分数阶微分方程m点边值问题正解的存在性 被引量:11
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作者 陆心怡 张兴秋 王林 《系统科学与数学》 CSCD 北大核心 2014年第2期218-230,共13页
给出了一类分数阶微分方程m点边值问题的格林函数,通过讨论其性质,运用uo有界算子和不动点指数理论,在与相应的线性算子第一特征值有关的条件下获得了分数阶微分方程多点边值问题正解及多个正解的存在性结果.
关键词 分数阶微分方程 格林函数 M点边值问题 正解 不动点指数
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分数阶微分方程多点边值问题的正解 被引量:9
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作者 钟文勇 《吉首大学学报(自然科学版)》 CAS 2010年第1期9-12,共4页
研究分数阶微分方程多点边值问题正解的存在性,利用动点定理,得到了边值问题至少存在1个正解和3个正解的充分条件.
关键词 分数阶微分方程 多点边值问题 正解 不动点
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Moving finite element methods for time fractional partial differential equations 被引量:9
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作者 JIANG YingJun MA JingTang 《Science China Mathematics》 SCIE 2013年第6期1287-1300,共14页
With the aim of simulating the blow-up solutions, a moving finite element method, based on nonuni- form meshes both in time and in space, is proposed in this paper to solve time fractional partial differential equatio... With the aim of simulating the blow-up solutions, a moving finite element method, based on nonuni- form meshes both in time and in space, is proposed in this paper to solve time fractional partial differential equations (FPDEs). The unconditional stability and convergence rates of 2 -a for time and r for space are proved when the method is used for the linear time FPDEs with a-th order time derivatives. Numerical exam-ples are provided to support the theoretical findings, and the blow-up solutions for the nonlinear FPDEs are simulated by the method. 展开更多
关键词 fractional partial differential equations moving finite element methods blow-up solutions
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Legendre-Weighted Residual Methods for System of Fractional Order Differential Equations
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作者 Umme Ruman Md. Shafiqul Islam 《Journal of Applied Mathematics and Physics》 2024年第9期3163-3184,共22页
The numerical approach for finding the solution of fractional order systems of boundary value problems (BPVs) is derived in this paper. The implementation of the weighted residuals such as Galerkin, Least Square, and ... The numerical approach for finding the solution of fractional order systems of boundary value problems (BPVs) is derived in this paper. The implementation of the weighted residuals such as Galerkin, Least Square, and Collocation methods are included for solving fractional order differential equations, which is broadened to acquire the approximate solutions of fractional order systems with differentiable polynomials, namely Legendre polynomials, as basis functions. The algorithm of the residual formulations of matrix form can be coded efficiently. The interpretation of Caputo fractional derivatives is employed here. We have demonstrated these methods numerically through a few examples of linear and nonlinear BVPs. The results in absolute errors show that the present method efficiently finds the numerical solutions of fractional order systems of differential equations. 展开更多
关键词 fractional differential equations System of fractional Order BVPs Weighted Residual Methods Modified Legendre Polynomials
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一类带积分边值条件的非线性分数阶微分方程的正解(英文) 被引量:8
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作者 薛益民 苏莹 苏有慧 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第2期251-256,共6页
利用Green函数的性质和Schauder不动点定理,本文研究一类带积分边值条件的非线性Caputo型分数阶微分方程边值问题,得到该边值问题正解的存在性定理,推广了相关结果,并举例说明了主要结果的适用性.
关键词 分数阶微分方程 积分边值条件 正解 不动点定理
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含积分边值条件的分数阶微分方程耦合系统正解的唯一性 被引量:8
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作者 薛益民 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2016年第6期1227-1232,共6页
本文研究了一类含积分边值条件的非线性分数阶微分方程耦合系统{~cD~αu(t)+f(t,u(t),v(t))=0,~cD~αv(t)+f(t,u(βt),v(βt))=0,u(0)=u′(0)=…=u^(n-2)(0)=u^(n)(0)=0,u(1)=λ∫01u(s)ds,v(0)=v′(0)=…=v^(n-2)(0)=v^(n)(0)=0,v(1)=... 本文研究了一类含积分边值条件的非线性分数阶微分方程耦合系统{~cD~αu(t)+f(t,u(t),v(t))=0,~cD~αv(t)+f(t,u(βt),v(βt))=0,u(0)=u′(0)=…=u^(n-2)(0)=u^(n)(0)=0,u(1)=λ∫01u(s)ds,v(0)=v′(0)=…=v^(n-2)(0)=v^(n)(0)=0,v(1)=λ∫01v(s)ds正解的唯一性.利用广义耦合不动点定理,本文得到了该边值问题正解的唯一性的充分条件,并在举例说明了定理的有效性. 展开更多
关键词 积分边值条件 分数阶微分方程 正解 耦合不动点
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分数阶泛函微分方程边值问题的耦合上下解方法 被引量:6
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作者 蹇星月 刘锡平 +1 位作者 贾梅 骆泽宇 《高校应用数学学报(A辑)》 北大核心 2019年第3期301-314,共14页
研究一类带时滞的分数阶泛函微分方程边值问题.首先将所研究的问题转化为积分方程形式,运用非线性分析理论证明了边值问题解的存在性与唯一性定理,产生了求边值问题解的单调迭代序列,并进行了误差估计.其次运用广义单调迭代技术和耦合... 研究一类带时滞的分数阶泛函微分方程边值问题.首先将所研究的问题转化为积分方程形式,运用非线性分析理论证明了边值问题解的存在性与唯一性定理,产生了求边值问题解的单调迭代序列,并进行了误差估计.其次运用广义单调迭代技术和耦合上下解方法,获得了边值问题解存在唯一的充分条件,并确定了解的取值范围.最后给出几个具体实例,用于说明所得到的结论具有较广泛的适应性. 展开更多
关键词 分数阶微分方程 泛函微分方程 边值问题 CAPUTO分数阶导数 耦合下上解 不动点定理
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EXISTENCE AND UNIQUENESS OF SOLUTIONS FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS WITH NON-SEPARATED TYPE INTEGRAL BOUNDARY CONDITIONS 被引量:6
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作者 Bashir Ahmad Juan J. Nieto Ahmed Alsaedi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2122-2130,共9页
In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results a... In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-Schauder degree theory. Some illustrative examples are also presented. We extend previous results even in the integer case q = 2. 展开更多
关键词 fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem LeraySchauder degree
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consistent Riccati expansion fractional partial differential equation Riccati equation modified Riemann–Liouville fractional derivative exact solution 被引量:7
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作者 黄晴 王丽真 左苏丽 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第2期177-184,共8页
In this paper, a consistent Riccati expansion method is developed to solve nonlinear fractional partial differential equations involving Jumarie's modified Riemann–Liouville derivative. The efficiency and power of t... In this paper, a consistent Riccati expansion method is developed to solve nonlinear fractional partial differential equations involving Jumarie's modified Riemann–Liouville derivative. The efficiency and power of this approach are demonstrated by applying it successfully to some important fractional differential equations, namely, the time fractional Burgers, fractional Sawada–Kotera, and fractional coupled mKdV equation. A variety of new exact solutions to these equations under study are constructed. 展开更多
关键词 Consistent Riccati Expansion Method and Its Applications to Nonlinear fractional Partial differential equations
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Moving collocation methods for time fractional differential equations and simulation of blowup 被引量:7
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作者 MA JingTang1 & JIANG YingJun2 1School of Economic Mathematics, Southwestern University of Finance and Economics, Chengdu 611130, China 2Department of Mathematics and Scientific Computing, Changsha University of Science and Technology, Changsha 410076, China 《Science China Mathematics》 SCIE 2011年第3期611-622,共12页
A moving collocation method is proposed and implemented to solve time fractional differential equations. The method is derived by writing the fractional differential equation into a form of time difference equation. T... A moving collocation method is proposed and implemented to solve time fractional differential equations. The method is derived by writing the fractional differential equation into a form of time difference equation. The method is stable and has a third-order convergence in space and first-order convergence in time for either linear or nonlinear equations. In addition, the method is used to simulate the blowup in the nonlinear equations. 展开更多
关键词 moving collocation methods time fractional differential equations BLOWUP
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一类变指数勒贝格空间中分数阶微分方程两点边值问题解的存在性
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作者 朱佳硕 王立波 《北华大学学报(自然科学版)》 CAS 2024年第2期148-155,共8页
研究一类变指数勒贝格空间L p(·)中具有Riemann-Liouville型导数的非线性分数阶微分方程边值问题。利用分段常值函数,将变指数勒贝格空间转化为经典的勒贝格空间,将问题模型转化为等价的第二类Fredholm积分方程,利用Schauder不动... 研究一类变指数勒贝格空间L p(·)中具有Riemann-Liouville型导数的非线性分数阶微分方程边值问题。利用分段常值函数,将变指数勒贝格空间转化为经典的勒贝格空间,将问题模型转化为等价的第二类Fredholm积分方程,利用Schauder不动点定理,得到了相应边值问题解的存在性结果。 展开更多
关键词 分数阶微分方程 SCHAUDER不动点定理 变指数勒贝格空间 Riemann-Liouville型导数
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能量泛函及Euler-Lagrange方程在图像降噪中的应用研究
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作者 王海燕 《佳木斯大学学报(自然科学版)》 CAS 2024年第6期173-175,180,共4页
研究了自适应分数阶偏微分方程修正模型的能量泛函及Euler-Lagrange方程。首先,定义了自适应分数阶偏微分方程修正模型的能量泛函,其中包含未知函数和拉格朗日乘子的集合。然后,通过求解能量泛函的极值方程,推导出了Euler-Lagrange方程... 研究了自适应分数阶偏微分方程修正模型的能量泛函及Euler-Lagrange方程。首先,定义了自适应分数阶偏微分方程修正模型的能量泛函,其中包含未知函数和拉格朗日乘子的集合。然后,通过求解能量泛函的极值方程,推导出了Euler-Lagrange方程。最后,讨论了Euler-Lagrange方程在自适应分数阶偏微分方程修正模型中的应用。 展开更多
关键词 分数阶微分方程 能量泛函 EULER-LAGRANGE方程 修正模型
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Pseudo S-Asymptotically(ω,c)-Periodic Solutions to Fractional Differential Equations of Sobolev Type
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作者 MAO Hang-ning CHANG Yong-kui 《Chinese Quarterly Journal of Mathematics》 2024年第3期295-306,共12页
In this paper,we firstly recall some basic results on pseudo S-asymptotically(ω,c)-periodic functions and Sobolev type fractional differential equation.We secondly investigate some existence of pseudo S-asymptotical... In this paper,we firstly recall some basic results on pseudo S-asymptotically(ω,c)-periodic functions and Sobolev type fractional differential equation.We secondly investigate some existence of pseudo S-asymptotically(ω,c)-periodic solutions for a semilinear fractional differential equations of Sobolev type.We finally present a simple example. 展开更多
关键词 Pseudo S-asymptotically(ω c)-periodic functions Evolution equations Sobolev type fractional differential equations Existence and uniqueness
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一类分数阶微分方程耦合系统边值问题解的存在性 被引量:6
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作者 薛益民 苏有慧 +1 位作者 刘洁 苏莹 《徐州工程学院学报(自然科学版)》 CAS 2018年第1期41-47,共7页
文章研究一类非线性Riemann-Liouville型分数阶微分方程耦合系统解的存在性.利用格林函数的性质和Guo-Krasnosel'skii's不动点定理,得到该耦合系统解存在性的充分条件.
关键词 分数阶微分方程 GREEN函数 耦合系统 不动点定理
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A Collocation Technique via Pell-Lucas Polynomials to Solve Fractional Differential EquationModel for HIV/AIDS with Treatment Compartment
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作者 Gamze Yıldırım Suayip Yüzbası 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期281-310,共30页
In this study,a numerical method based on the Pell-Lucas polynomials(PLPs)is developed to solve the fractional order HIV/AIDS epidemic model with a treatment compartment.The HIV/AIDS mathematical model with a treatmen... In this study,a numerical method based on the Pell-Lucas polynomials(PLPs)is developed to solve the fractional order HIV/AIDS epidemic model with a treatment compartment.The HIV/AIDS mathematical model with a treatment compartment is divided into five classes,namely,susceptible patients(S),HIV-positive individuals(I),individuals with full-blown AIDS but not receiving ARV treatment(A),individuals being treated(T),and individuals who have changed their sexual habits sufficiently(R).According to the method,by utilizing the PLPs and the collocation points,we convert the fractional order HIV/AIDS epidemic model with a treatment compartment into a nonlinear system of the algebraic equations.Also,the error analysis is presented for the Pell-Lucas approximation method.The aim of this study is to observe the behavior of five populations after 200 days when drug treatment is applied to HIV-infectious and full-blown AIDS people.To demonstrate the usefulness of this method,the applications are made on the numerical example with the help of MATLAB.In addition,four cases of the fractional order derivative(p=1,p=0.95,p=0.9,p=0.85)are examined in the range[0,200].Owing to applications,we figured out that the outcomes have quite decent errors.Also,we understand that the errors decrease when the value of N increases.The figures in this study are created in MATLAB.The outcomes indicate that the presented method is reasonably sufficient and correct. 展开更多
关键词 Collocation method fractional differential equations HIV/AIDS epidemic model Pell-Lucas polynomials
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